using Grpc.Net.Client.Configuration;
using MareSynchronosShared.Data;
using MareSynchronosShared.Metrics;
using MareSynchronosShared.Services;
using MareSynchronosShared.Utils;
using MareSynchronosStaticFilesServer.Controllers;
using MareSynchronosStaticFilesServer.Services;
using MareSynchronosStaticFilesServer.Utils;
using MessagePack;
using MessagePack.Resolvers;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc.Controllers;
using Microsoft.AspNetCore.Server.Kestrel.Core;
using Microsoft.AspNetCore.SignalR;
using Microsoft.EntityFrameworkCore;
using Microsoft.IdentityModel.Tokens;
using Prometheus;
using System.Text;

namespace MareSynchronosStaticFilesServer;

public class Startup
{
    private bool _isMain;
    private readonly ILogger<Startup> _logger;

    public Startup(IConfiguration configuration, ILogger<Startup> logger)
    {
        Configuration = configuration;
        _logger = logger;
        var mareSettings = Configuration.GetRequiredSection("MareSynchronos");
        _isMain = string.IsNullOrEmpty(mareSettings.GetValue(nameof(StaticFilesServerConfiguration.MainFileServerAddress), string.Empty));
    }

    public IConfiguration Configuration { get; }

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddHttpContextAccessor();

        services.AddLogging();

        services.Configure<StaticFilesServerConfiguration>(Configuration.GetRequiredSection("MareSynchronos"));
        services.Configure<MareConfigurationAuthBase>(Configuration.GetRequiredSection("MareSynchronos"));
        services.Configure<KestrelServerOptions>(Configuration.GetSection("Kestrel"));
        services.AddSingleton(Configuration);

        var mareConfig = Configuration.GetRequiredSection("MareSynchronos");

        services.AddSingleton(m => new MareMetrics(m.GetService<ILogger<MareMetrics>>(), new List<string>
        {
        }, new List<string>
        {
            MetricsAPI.GaugeFilesTotalSize,
            MetricsAPI.GaugeFilesTotal,
            MetricsAPI.GaugeFilesUniquePastDay,
            MetricsAPI.GaugeFilesUniquePastDaySize,
            MetricsAPI.GaugeFilesUniquePastHour,
            MetricsAPI.GaugeFilesUniquePastHourSize,
            MetricsAPI.GaugeCurrentDownloads,
            MetricsAPI.GaugeDownloadQueue,
        }));
        services.AddSingleton<CachedFileProvider>();
        services.AddSingleton<FileStatisticsService>();
        services.AddSingleton<RequestFileStreamResultFactory>();

        services.AddHostedService(m => m.GetService<FileStatisticsService>());
        services.AddHostedService<FileCleanupService>();

        services.AddDbContextPool<MareDbContext>(options =>
        {
            options.UseNpgsql(Configuration.GetConnectionString("DefaultConnection"), builder =>
            {
                builder.MigrationsHistoryTable("_efmigrationshistory", "public");
            }).UseSnakeCaseNamingConvention();
            options.EnableThreadSafetyChecks(false);
        }, mareConfig.GetValue(nameof(MareConfigurationBase.DbContextPoolSize), 1024));

        var noRetryConfig = new MethodConfig
        {
            Names = { MethodName.Default },
            RetryPolicy = null,
        };

        services.AddOptions<JwtBearerOptions>(JwtBearerDefaults.AuthenticationScheme)
            .Configure<IConfigurationService<MareConfigurationAuthBase>>((o, s) =>
            {
                o.TokenValidationParameters = new()
                {
                    ValidateIssuer = false,
                    ValidateLifetime = false,
                    ValidateAudience = false,
                    ValidateIssuerSigningKey = true,
                    IssuerSigningKey = new SymmetricSecurityKey(Encoding.ASCII.GetBytes(s.GetValue<string>(nameof(MareConfigurationAuthBase.Jwt)))),
                };
            });

        services.AddAuthentication(o =>
        {
            o.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
            o.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
            o.DefaultScheme = JwtBearerDefaults.AuthenticationScheme;
        }).AddJwtBearer();

        services.AddAuthorization(options =>
        {
            options.FallbackPolicy = new AuthorizationPolicyBuilder().RequireAuthenticatedUser().Build();
            options.AddPolicy("Internal", new AuthorizationPolicyBuilder().RequireClaim(MareClaimTypes.Internal, "true").Build());
        });

        if (_isMain)
        {
            services.AddGrpc(o =>
            {
                o.MaxReceiveMessageSize = null;
            });

            services.AddSingleton<IConfigurationService<StaticFilesServerConfiguration>, MareConfigurationServiceServer<StaticFilesServerConfiguration>>();
        }
        else
        {
            services.AddSingleton<IConfigurationService<StaticFilesServerConfiguration>, MareConfigurationServiceClient<StaticFilesServerConfiguration>>();
            services.AddHostedService(p => (MareConfigurationServiceClient<StaticFilesServerConfiguration>)p.GetService<IConfigurationService<StaticFilesServerConfiguration>>());
        }

        services.AddSingleton<IConfigurationService<MareConfigurationAuthBase>, MareConfigurationServiceClient<MareConfigurationAuthBase>>();

        services.AddSingleton<ServerTokenGenerator>();
        services.AddSingleton<RequestQueueService>();
        services.AddHostedService(p => p.GetService<RequestQueueService>());
        services.AddControllers().ConfigureApplicationPartManager(a =>
        {
            a.FeatureProviders.Remove(a.FeatureProviders.OfType<ControllerFeatureProvider>().First());
            if (_isMain)
            {
                a.FeatureProviders.Add(new AllowedControllersFeatureProvider(typeof(MareStaticFilesServerConfigurationController), typeof(CacheController), typeof(RequestController), typeof(ServerFilesController)));
            }
            else
            {
                a.FeatureProviders.Add(new AllowedControllersFeatureProvider(typeof(CacheController), typeof(RequestController)));
            }
        });

        services.AddHostedService(p => (MareConfigurationServiceClient<MareConfigurationAuthBase>)p.GetService<IConfigurationService<MareConfigurationAuthBase>>());

        services.AddSingleton<IUserIdProvider, IdBasedUserIdProvider>();
        var signalRServiceBuilder = services.AddSignalR(hubOptions =>
        {
            hubOptions.MaximumReceiveMessageSize = long.MaxValue;
            hubOptions.EnableDetailedErrors = true;
            hubOptions.MaximumParallelInvocationsPerClient = 10;
            hubOptions.StreamBufferCapacity = 200;
        }).AddMessagePackProtocol(opt =>
        {
            var resolver = CompositeResolver.Create(StandardResolverAllowPrivate.Instance,
                BuiltinResolver.Instance,
                AttributeFormatterResolver.Instance,
                // replace enum resolver
                DynamicEnumAsStringResolver.Instance,
                DynamicGenericResolver.Instance,
                DynamicUnionResolver.Instance,
                DynamicObjectResolver.Instance,
                PrimitiveObjectResolver.Instance,
                // final fallback(last priority)
                StandardResolver.Instance);

            opt.SerializerOptions = MessagePackSerializerOptions.Standard
                .WithCompression(MessagePackCompression.Lz4Block)
                .WithResolver(resolver);
        });

        // configure redis for SignalR
        var redisConnection = mareConfig.GetValue(nameof(ServerConfiguration.RedisConnectionString), string.Empty);
        signalRServiceBuilder.AddStackExchangeRedis(redisConnection, options => { });

        services.AddHealthChecks();
    }

    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        app.UseHttpLogging();

        app.UseRouting();

        var config = app.ApplicationServices.GetRequiredService<IConfigurationService<MareConfigurationAuthBase>>();

        var metricServer = new KestrelMetricServer(config.GetValueOrDefault<int>(nameof(MareConfigurationBase.MetricsPort), 4981));
        metricServer.Start();

        app.UseHttpMetrics();

        app.UseAuthentication();
        app.UseAuthorization();

        app.UseEndpoints(e =>
        {
            if (_isMain)
            {
                e.MapGrpcService<GrpcFileService>();
            }
            e.MapHub<MareSynchronosServer.Hubs.MareHub>("/dummyhub");
            e.MapControllers();
            e.MapHealthChecks("/health").WithMetadata(new AllowAnonymousAttribute());
        });
    }
}